Pete lives in the Pohangina Valley, Aotearoa/New Zealand and writes about travelling and people, mountains and other wild places, photography, Aotearoa-NZ, natural history, strangeness and possibility, wondering, life in general and a swag of other stuff. ('Paw-HUNG-in-uh' is a close enough pronunciation.)

07 September 2008

Flipping rocks

A magpie warbles behind the sheds; starlings scuffle in the box surrounding the header tank (they're nesting there, as usual). The monotonous cheep of sparrows; a whoosh of wings as a kereru swoops over the paddock where blackbirds and thrushes peer and tug at worms. Something hops on the iron roof and the dogs whine and bark. Only the kahu remains silent, floating in the early morning sky, circling over the river flats, gaining height near the edge of the terrace. The front paddock glitters with heavy dew, then, as the sun reaches down from the north-east, the sparkling dew retreats into diminishing shadows. The remains of the night vanish into the past. Conservation Week 2008 and International Rock Flipping Day have begun.

Conservation Week runs from 7–14 September but International Rock Flipping Day lasts just 24 hours — well, at least officially: any day's a good day to learn more about what lives in your back yard. Here in Aotearoa we're the first in the world to get going. It's certainly a better day for it than last year, when I checked under a few rocks in the drizzly showers, finding little other than a few harvestmen and a large ground hunting spider. Then, I'd had reservations about disturbing these small lives — I still do — but the instructions are clear: do it with care, record what you find, replace the rock gently, and try to minimise the disturbance.

Dew still saturates much of the steep, south-facing slope that drops to Te Awaoteatua stream, and the memory of last night's cold lingers along the ragged track. Amelie and I move carefully downhill over the slippery grass, checking a few promising stones, but all we find are big, fat earthworms in the sodden soil. A crane fly larva, too, but few animals are less photogenic than a round, dun maggot. It's not even spectacularly ugly, just boringly dull. Ironically, if it survives it will transform into an insect of strange and impossibly delicate beauty; this near-formless, subterranean, legless grub will become an attenuated adult, its body clearly constructed of distinct, chitin-plated parts, supported on legs far longer than its body and as fine as human hair; it will rise into the sky on long transparent wings marked with a strikingly graphic pattern of veins. New Zealand has over 550 species of crane flies (Tipulidae), some flightless, some — possibly many — still unknown to science, some predatory, some vegetarian, some large, some small. The smaller crane flies are often swatted by people who, knowing no better and unwilling to look closely, call them mosquitoes. Yet none bite or sting people.

I replace the rock gently and carry on down the slope, towards the rocks, tussocks, and rotting logs emerging into the sunlight from the shadow of the slope."Aren't you going to check these rocks?" Amelie calls from near the track." Nah, there's nothing interesting under them. Only worms and stuff. It's too wet."" Well what about this one? It's got some lovely moss on it.""Moss! Moss isn't an animal!""But it's beautiful," she says. "Look at the all the colours and textures, all these lovely details."

I, however, have reverted to the small boy mindset. Moss does not interest small boys. Things with legs, especially things that might do harm to other small things, are vastly more exciting than moss, or indeed plants in general. Plants just sit there and grow, and one cannot even see them grow. This is wrong, of course, but the selective deafness of small — and large — boys allows no argument.

"What do you hope to find down there anyway," she calls, "— a tuatara?""Maybe," I say, becoming stubbornly unreasonable, "or maybe a previously undiscovered population of native frogs."Both are as likely as all the world's small boys suddenly preferring the flipping of rocks to their playstations and dreams of rockstardom — but one never knows. One must hope.

Beneath several rocks I find an earthworm, nothing, and more nothing. But, carefully easing over the next rock, I find a small, elegant spider — and a skink.

It might not be a tuatara, but it's close enough[1]. And it's exciting enough for this small boy.

Notes:1. They're both reptiles, but while skinks are lizards, tuatara are not.

Photos (click to enlarge them):1. Kereru, Hemiphaga novaeseelandiae, Pohangina valley.2. The small spider, which I haven't yet identified.3. The skink. We replaced it carefully under the rock and trust it won't be too disturbed by becoming internationally famous.

Thank you Bob. Aotearoa's diversity of land birds is pretty poor compared to many other countries, especially those in the tropics, but many of our birds are no less beautiful or fascinating. I'm pleased the post brought back good memories for you.

Lus, the skink was probably a bit cold early in the morning, but it started to move around within a minute or two of being uncovered. I doubt a hibernating lizard would have been so quick to get going, but at least it allowed me a few photos. However, even when they're fully active, they do stop and remain utterly motionless at least for a few seconds at a time, so photos are possible if you're set up and anticipating the stop.

Dave, it certainly surprised me, as it's been quite a while since I've seen a skink (I think the last was actually in Malawi in May '06).

Zhoen, yeah, I admit it. Moss is nice when you look closely, but when it comes to human attention I guess it competes with skinks in much the same way as acacias compete with rhinos and other charismatic megafauna.

Deborah, thanks, and you might be right about the tail. I'll see if I can find an expert opinion — I'm outside my own expertise here.

Thanks for leaving a comment on my blog and leading me to this fantastic site. I will enjoy following your blog and learning about nature on the other side of the world. My husband lived in Gore, New Zealand and loved the country very much. We hope to go back and spend a year some time.

Thank you Beth. New Zealand's a wonderful place, particularly if you love the non-human world. I'm lucky indeed to live here.

Cheers Samurai. Kereru, our native pigeons, are certainly impressive birds, particularly when the light catches them as it did for this photo. I acquired my fondness for insects very early, but anyone who gets a chance to look closely at something like a robber fly must be at least impressed (this post has a photo of one).

Thanks Jen :^) Always nice to share these things with people who appreciate them.

Thank you Susan. Plenty more photos similar to these if you feel like browsing through the blog :^)

Great post with beautiful photos. The actual 9 year old boy I flipped rocks with was full of hope about every rock we overturned and could have gone on all day. We didn't find anything as beautiful as your skink, but the search alone seemed satisfying. What a fun event--and I'm glad to know about your blog.

Hugh, skinks are such fascinating animals. Encountering one's always a thrill, although I have to say I find geckos particularly fascinating — they're even more like miniature dragons. I've made some enquiries about the i.d. of this skink, and will update the post when I get a response.

Thanks Julie. It's great to hear about the 9-year-old's enthusiasm (although it doesn't surprise me). Pleased, too, that you enjoyed it so much :^)

A little bird suggested I take a look at your photo of a big bird. It's beautiful.

Saturday was Ruahine Leaf-Turning Day - a rather less-well publicised event. I was trying to decide whether I was looking at mataii or miro. It seems this is easy if the tree has berries on it - or if you're fortunate enough to have met both. But as a novice faced with berry-less specimens of a single species I was partly reduced to trying to decide whether the undersides of the leaves could be considered whitish or not... I rather suspect I was looking at miro, but I shall have to wait until I have met both to settle the question!

PJ, there's no real substitute for visiting NZ in person, but it's nice to know I've got you interested. Plenty more if you feel like browsing through older posts; the index and summary's probably a good way to find posts that might interest you.

No worries, Sherry — I'm a bit late posting a reply! Thanks for the kind words; much appreciated.

Anne-Marie, yes, I have to admit moss is nice. It also harbours a wonderful micro-fauna (tardigrades, for example), although getting a good look at those tiny animals requires pulling the moss apart. However, I'm pretty happy with the skink, although it certainly doesn't match your sighting of a karearea the other day.

CT, thanks, and I suspect I know who that little bird is :^) I have to admit my ability to identify plants isn't up to par, but I could probably recognise a juvenile miro — they're quite beautiful. When they get old enough to produce fruit, they're apparently favoured by kereru, who gorge themselves silly.

I like the idea of International Rock Flipping Day - i assume you mean the practice of turning over rocks to see the animals beneath (something we did in school to find woodlice for class) - as opposed to the kids today (that makes me sound old) who think that flipping rocks involves throwing them at your windows/washing line/both. Fantastic photo of the spider - sometimes it's about being in the right place at the right place, but i guess your local knowledge helps a lot here?

I'm a little late in coming to your party, but I must say, I found your rock-flipping post to be the coolest of all the ones I have read. I love the image of a stubborn little boy, determined to look at the rocks HE wants to look at and hoping for a monster instead of an ant. Your bird photo is fabulous, and I think the skink is the best find of all.

DFT Pixies, yes, that's the kind of rock flipping I mean, although I'd be surprised if kids somewhere didn't use IRF Day as an excuse for the other sort. Actually, there's yet another kind, which I suppose could loosely be called flipping: namely, that of skipping stones across water. Great fun, especially when indulged in with kids (big and small). As for the spider, thanks, and I have to say I was indeed expecting to find spiders of some sort. They're a pretty safe bet around here.

Thanks Kathi, that's a very generous comment. But everyone who joined in added something; interesting finds or different perspectives, and sometimes both. All those add up to a complex and intriguing picture of backyards around the world.

Kia ora Pete, That picture blows me away! You and Amelie seem to have a knack with the bird life at the moment. Early morning and i am listening to our resident tui's greeting the day. Cheers Pete.Rangimarie,robb

Pete, you've solved a mystery. We've always had non-biting "mosquitoes" around the house. I knew no better and didn't look closely enough, did I? :-( However, because I'd realised that they didn't bite, I mostly let them be.

We quite often find large crane flies inside and, when I'm able to catch them without harming them, I put them outdoors. This morning I found a similarly delicate, long-legged, tiny creature in the shower with me: a harvestman (the introduced Pholcus phanalangioides, according to a photograph I tracked down). I was relieved to discover that it had not only survived the deluge, which luckily hadn't been too hot, but that it was also undamaged. I placed it on some small flowers in a vase on the kitchen windowsill to finish drying off, intending to come back later and photograph it, but I was unexpectedly called away from home and when I'd returned it had disappeared.

I'm puzzled by one thing, though. Information I found said that harvestmen have no spinnerets and don't produce silk, yet this one, when it slipped off the flower, hung by a thread too fine for me to see and climbed back up it. I then watched it choose a place on which to settle - a fascinating process. Its jointed legs, many times longer than its body and barely thicker than one of my own hairs, repeatedly reached around the edge of the petals from underneath, feeling for a firm purchase on top where it finally came to rest. I was interested to note that the first and fourth pairs of legs were longer than the two middle pairs.

Cheers Robb. We've been enjoying the good weather today; plenty of kereru around and a few korimako as well. Will catch up with you and Tara soon. :^)

Peregrina, that's easily solved. “Daddy longlegs” is a common name used for three quite different groups of invertebrates: crane flies, which are true flies (insects in the Order Diptera); harvestmen, which are arachnids (in the Order Opiliones) but are not spiders; and the true spider Pholcus phalangioides (Order Araneae). Your P. phalangioides most definitely produces silk, as you saw; I've also seen them swathing jumping spiders and even white-tailed spiders in silk. Harvestmen don't produce silk.

These common names have no formal standing, so their meaning arises from how they're used — for example, if enough people used “harvestman” to refer to P. phalangioides (heaven forbid), that would eventually become an accepted common name. However, I trust that won't happen; the common terminology is already confused enough.

My suggestion would be to use “harvestman” solely for Opiliones; “crane flies” or “tipulids” ( from the Family name Tipulidae) for crane flies; and “Pholcus”, “cellar spider”, or, at a pinch, “daddy longlegs spider” for P. phalangioides, and never to use the unqualified term “daddy longlegs”.

Thank you for putting me right, Pete. I was fooled by finding a thumbnail photograph labelled "Daddy Longlegs" which I recognised as the creature I was trying to identify, beside a paragraph on harvestmen and below an untitled photograph of a native harvestman. The information on the website (where else would one search for - some, anyway - arachnids?) was of a general nature, including spiders, mites and pseudoscorpions. Further trawling through websites produced the same, enlarged, photograph with identification, but I didn't read the accompanying text which would have made it clear that what I had was a spider. I must admit that I'd noticed a discrepancy between Opiliones for the native harvestman and Pholcus for my specimen, but put it down to the fact that the harvestman species found in gardens (as opposed to the natives only in forest) are exotic. I guess my knowledge of both biology and taxonomy is abysmal, but I'm learning. Thanks again, Pete.

I found the P. phalangioides yesterday morning in a corner above the top of a cupboard - just the sort of place they're likely to be found indoors, apparently. I was able to capture and photograph it, although had it seemed agitated I was prepared to release it immediately. However, it sat perfectly still on the back of a large brown leaf, allowing slow exposures for good depth of field. (No instant feedback as to my success, though! Fingers crossed.) I put it outside onto a large shrub in a sheltered position.

Its middle pairs of legs are longer than I had thought. It seems to have a habit of drawing them up so that they appear much shorter.

How did I miss Rock Flipping Day? I promised myself last year that I wouldn't miss it again and yet somehow I managed to. Perhaps I was waiting for someone else to flip over the rock I've been under?

Flipping rocks is an exciting activity and it's amazing the range of emotions you can feel each time the world underneath is revealed. My greatest joy was discovering a baby common mole crouched there apparently in utter astonishment at my sudden appearance. My greatest shock was coming upon what I assumed was some kind of enormous, slow-moving, ochre-colored leach or worm or amoeba, more than two meters long but only 5 millimeters wide when it slowly flowed away into the bushes. It is easy to realize that you really know nothing about the world at all when you look under rocks.

Peregrina, glad you've found the investigation fascinating. Common names, although often useful — and generally far more pronounceable than the scientific name — can cause a great deal of confusion.

Miguel, a mole would surely have been a brilliant find. I can imagine its astonishment; rather similar to mine if I'd found a mole, I suppose (no moles in Aotearoa). Incidentally, the occupation of one of my Scottish ancestors is listed in census records as "mole-catcher". Now, I'll be hoping no one flips my house while I'm asleep tonight. "Astonishment" wouldn't really be the right word...

About Pete

Pete lives in the Pohangina Valley, Aotearoa/New Zealand. His primary blog, Pohanginapete, is about travelling and people, mountains and other wild places, photography, Aotearoa-NZ, natural history, strangeness and possibility, wondering, life in general and a swag of other stuff. It has lots of photographs, too.
He updates his photoblog, The Ruins of the Moment, every few days (with the occasional hiatus).